principle-type-system-discipline
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
Skill by backnotprop
Install
Works with Claude Code, Claude apps, Codex, Cursor, Gemini CLI, GitHub Copilot, VS Code, OpenCode, Goose, Windsurf. Read the repository before you give any tool access to your data.
npx agentmarket install skill/backnotprop-principle-type-system-discipline
Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.
Get the weekly diff
The weekly diff: one email a week with new agent tools, notable updates and grade changes, plus security alerts for tools you follow. Double opt-in, one-click unsubscribe.
About
Use cases: design, data, writing
Reviews
Write a reviewNo reviews yet. Installed it? Reviews come from verified installers only. How reviews work
Permissions
What this skill can do and what it asks for, from its SKILL.md. Checked Oct 25, 2026.
- Tools
- No tools found
- Secrets
- None asked for
- Install scripts
- None found
Network hosts it talks to 1
codeload.github.com· found in install command
Files it touches
~/.claude/skills/principle-type-system-discipline
What's inside
- Skill name
principle-type-system-discipline- Description
- Apply when designing types, reviewing a function signature, or writing code in any statically-typed language. Make illegal states unrepresentable, brand semantic primitives, parse external data at boundaries, exhaust variants, derive from authoritative schemas.
- License
- MIT
- Instructions
- 9 lines in SKILL.md · view on GitHub
Files (1)
- SKILL.md
SKILL.md (first lines)
# Type System Discipline Make the compiler reject impossible states, mismatched primitives, and unhandled variants. Prefer defining errors and special cases out of existence over proliferating handlers. For TypeScript syntax, see the `typescript-best-practices` skill. - **Brand semantic primitives.** `UserId` and `OrderId` are strings underneath but should not be interchangeable. Give each its own type, such as a branded intersection in TypeScript or a newtype elsewhere. Validate once at creation, trust the type downstream. If two arguments share a primitive type but mean different things, brand them. - **External data is untyped until parsed.** RPC payloads, JSON, IPC messages, CLI args, config files, environment variables, database rows. Have a parse function at every boundary that turns unstructured input into the typed model. The **boundary-discipline** principle skill says where to put validation. - **Derive types from authoritative schemas.** When a protocol buffer, OpenAPI spec, GraphQL schema, database migration, design-token file, or another file owns a shape, derive from it instead of hand-rolling a parallel type. See the **encode-lessons-in-structure** principle skill.
From backnotprop/pstack, MIT.
More from backnotprop/pstack
- 0.769score
statechart
backnotprop
Draw how any system moves between states, such as a product flow, a protocol, or a service, as a Mermaid statechart from a TLA+ model.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.769score
show-me-your-work
backnotprop
Keep a reviewable decision trail for long-running or unattended work: a TSV log with one row per decision (what, why, evidence, result).
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.769score
reflect
backnotprop
Spawn three parallel review subagents over the active transcript, surface learnings, and route each to a concrete edit on an existing skill.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.769score
why
backnotprop
Use for 'why does X work this way', 'why we picked Y', design rationale, regressions, postmortems, or data-backed thresholds.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.768score
typescript-best-practices
backnotprop
TypeScript best practices.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.766score
poteto-help
backnotprop
Guides users through pstack setup, /poteto-mode, and picking the skill, playbook, or principle for a task.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.764score
maintain-formal-verification-skill
backnotprop
Bring a project's formal verification back in line with the code after the code changes: find the commits that touched verified code, update the model…
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.761score
technical-writing
backnotprop
Layered technical-writing standard: Diátaxis structure, Google developer style sentences, STE instruction rules, Global English syntax.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.761score
swarm
backnotprop
Fan out N parallel workers, drain them, and return one report.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.761score
setup-pstack
backnotprop
Configure which models pstack uses per role and at what reasoning budget.
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.760score
recall
backnotprop
Reconstruct your recent working context from your own chat history, live state, and the shared record (user reports, prior fixes, incidents), then hand back a…
SkillAFreshness: A★ 2.7KClaude Code +9 - 0.758score
principle-model-the-domain
backnotprop
Apply when writing stateful logic, or when code branches a lot or repeats a shape assumption across files.
SkillAFreshness: A★ 2.7KClaude Code +9
Signals
- Stars
- 2,694
- Forks
- 207
- Open issues
- 1
- Last commit (this folder)
- Oct 19, 2026 (9 days ago)
From GitHub (fetched Oct 24, 2026).
Details
- License
- MIT
- Repository
- github.com/backnotprop/pstack
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
- Source
- GitHubgithub-graphql
Same skill elsewhere
Copies of this SKILL.md published by others; search shows only one of them.
- 0.396score
principle-type-system-discipline
dsebban
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
SkillAFreshness: A★ 68Claude Code +9 - 0.382score
principle-type-system-discipline
jiangkoumo
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
SkillAFreshness: A★ 27Claude Code +9 - 0.360score
principle-type-system-discipline
creedants
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
SkillAFreshness: A★ 15Claude Code +9 - 0.344score
principle-type-system-discipline
dhruvsaxena1998
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
SkillAFreshness: A★ 1Claude Code +9 - 0.334score
principle-type-system-discipline
matthewyjiang
Apply when designing types, reviewing a function signature, or writing code in any statically-typed language.
SkillAFreshness: AClaude Code +9
More from backnotprop
- 0.786score
plannotator-visual-explainer
backnotprop
Generate self-contained HTML visualizations with Plannotator theming.
SkillAFreshness: A★ 9.6KClaude Code +9 - 0.782score
release-plannotator
backnotprop
Prepare and execute a Plannotator release — draft release notes with full contributor credit, bump versions across all package files, build in dependency…
SkillAFreshness: A★ 9.6KClaude Code +9 - 0.781score
review-renovate
backnotprop
Review Renovate bot PRs that update GitHub Actions dependencies.
SkillAFreshness: A★ 9.6KClaude Code +9 - 0.781score
plannotator
backnotprop
Reference for using Plannotator (its `plannotator` tool when you have one, otherwise the CLI): plan review, code review, annotating files, URLs, folders, and…
SkillAFreshness: A★ 9.6KClaude Code +9 - 0.778score
plannotator-annotate
backnotprop
Open Plannotator's annotation UI for a markdown file, plain-text config file (.yaml, .json, .toml, .ini, .csv, .log, …), HTML file, URL, or folder and then…
SkillAFreshness: A★ 9.6KClaude Code +9 - 0.778score
update-deps
backnotprop
Audit and update npm/Bun dependencies with supply chain integrity checks — verifies maintainers, publish age, tarball diffs, and provenance before bumping.
SkillAFreshness: A★ 9.6KClaude Code +9
Cite this page
principle-type-system-discipline skill. Agent Mart. https://agentmart.dev/skills/backnotprop-principle-type-system-discipline (last updated 2026-10-24)